If you
can't get a CDP1861 Pixie graphics chip then don't despair - the Spare Time
Gizmos STG1861 emulator is built on a small daughter card that fits on top of
the main Elf 2000 board and plugs into the CDP1861 socket. The STG1861 uses two PLDs and two 74HCxx TTL chips to emulate the original CDP1861 and is an
exact functional replacement for the CDP1861. No software changes are
required and, in fact, the software can't tell the difference!

By the way, the usefulness of the STG1861 isn't confined to the Elf 2000 -
the STG1861 can replace the CDP1861 in in any application, including the
original P-E Elf and its many clones.

The
Disk/UART/RTC board is a PCB about 3.5" square that attaches to the upper right corner of the Elf 2000 board. It connects to the main board with
a 24 pin stacking connector and mounts to the main board with 0.625" stand offs.
Additional I/O boards can still be stacked on top of the disk board, and the
disk board doesn't interfere with the STG1861 Pixie Replacement board nor does
it obscure the TIL311 displays.

The Disk/UART/RTC board contains a CompactFlash interface, including an onboard CompactFlash socket, that's software compatible with the one Mike Riley
uses for his ElfOS system. A standard 40 pin male header is provided for
connecting a ribbon cable and an external CompactFlash drive.

The Disk/UART/RTC board also contains an 8250/16450/16550 UART chip (the same one that's used in the PC) with a
programmable baud rate generator and partial modem control. The baud rate
generator may be programmed for any speed, standard or otherwise, from 110 to
115,000bps.

And finally, the Disk/UART/RTC board contains a time of day clock and
non-volatile RAM using the DS12887A, DS12887, DS1287 or MC146818A chips. These
are the same clock/calendar chip that is (or was) used in the PC. Each one can
keep track of the time of day even with the power off, and provides up to 128
bytes of non-volatile RAM.

The Spare Time Gizmos Monitor EPROM contains a full set of power on self test
(POST) diagnostics for the serial port, RTC, NVR and CompactFlash interface.
The Monitor EPROM also allows the UART to be used as the console serial port,
rather than the "bit banged" motherboard port and can auto baud any standard baud
rate from 2400 thru 19200bps. When used as a console, the UART works with
the built in EPROM languages (BASIC, Forth, EDIT/ASM) and also ElfOS.
Finally, the Monitor can save various settings, including the last baud rate and
an automatic bootstrap flap, in the non-volatile RAM. The automatic
bootstrap flag allows the monitor to boot directly to ElfOS on power up with out
any console interaction.

COSMAC Elf 2000 Monitor version 60 or later is
required to fully support this board.

The
Spare Time Gizmos Elf 2000 VT1802 video board is able to generate a real 80
column by 24 line text display on a CGA compatible CRT or RS-170 composite video
monitor. Reverse video, underline, and blinking video attributes and four
different character sets may be selected and simultaneously displayed under
software control. With the proper character generator ROM, the hardware is also
capable of displaying simple line and box drawing graphics characters.

The VT1802 uses the 1802's DMA system to fetch ASCII characters directly from
a buffer anywhere in RAM or EPROM. Unlike the CDP1861 Pixie video, the video
timing for the video card is independent of the CPU clock and any CPU crystal
frequency up to the CPU's maximum may be used. With a 3 MHz CPU clock, the DMA
and interrupt service for the 80 column card uses approximately 50% of the total
CPU time.

The Spare Time Gizmos Elf 2000 Monitor EPROM contains a VT52 terminal
emulator that works with the VT1802 and takes care of all the work necessary for
maintaining the display. The firmware allows the video display to be used
independently of the console terminal or, if the GPIO PS/2 Keyboard Interface is
also present, as a replacement for the console terminal. The video display works
with BASIC, Forth, EDIT/ASM, or ElfOS.

COSMAC Elf 2000 Monitor version 85 or later is
required to fully support this board.

Please read the Spare Time Gizmos
store policies before ordering. Shipping charges shown are for
the US only - international customers please
inquire before ordering. Sales tax must be charged on all shipments to
California addresses.

P/N

Description

Price

PC Boards and Programmed parts for for the Elf 80
Column Video
card
are no longer available.

If you do not wish to pay by Google Checkout, please
contact us with your needs and we'll be happy to accept payment by personal
check or money order.

The
Spare Time Gizmos Elf 2000 General Purpose I/O board (GPIO), integrates three
independent I/O functions onto a single card. The first GPIO function is a PS/2
keyboard interface. A single chip microprocessor on the GPIO card handles the
PS/2 protocol, converts the keystrokes to ASCII, and presents the data the 1802
as if it were a simple parallel ASCII keyboard.

The GPIO card also contains an 8255 programmable parallel I/O (PPI) chip. The
8255 is a very popular general purpose parallel interface chip that provides 24
I/O bits. The bits can be configured as inputs, outputs, or as an 8 bit
bidirectional port with or without handshaking.

And finally, the GPIO card contains a speaker for generating tones. Arbitrary
tones and even simple music may be generated by 1802 software either by toggling
the Q bit or thru an output port. The speaker logic also contains a fixed
frequency oscillator that may be used to generate simple beeps without any
software intervention.

Note that these three GPIO subsystems are functionally independent and if you
donít require all of them you can easily omit the unused parts when you build
your GPIO card.

COSMAC Elf 2000 Monitor version 85 or later is required
to fully support this board.

P/N

Description

Price(S&H)

PC Boards and Programmed parts for for the Elf GPIO
card
are no longer available.

This option replaces the standard toggle switch Elf 2000 front panel with a
push button keypad similar to the Quest Super Elf. Sixteen keys are
provided for direct hexadecimal entry, and five additional buttons (RESET,
RUN, LOAD, MP and INPUT) are for mode control.
The five function keys are illuminated from behind by T1 LEDs, and there is a
small beeper that generates a short key click whenever any key is pressed. The Hexadecimal Keypad plugs into the same 20 pin switch panel header already
present on the COSMAC Elf 2000. No changes or modifications to the Elf
2000 are required.

Please note that we only have non-illuminated push buttons for sale.
I'm afraid I don't know where to get the illuminated variety - if you find a
source, please post to the newsgroup and let us all know.

Please read the Spare Time Gizmos store
policies before ordering. Shipping charges shown are for the US
only - international customers please
inquire before ordering. Sales tax must be charged on all shipments to
California addresses.

P/N

Description

Price(S&H)

PC Boards and Programmed parts for for the Elf
Keypad
are no longer available.

Not
an accessory as such, but a complete Elf in itself, the Embedded Elf is a
slightly simplified and much smaller version of the Elf 2000. The Embedded Elf
is exactly the same size and form factor as the Elf 2000 daughter cards, such as
the Disk/UART/RTC card, the 80 Column Video card, or the GPIO General Purpose
I/O card. The Embedded Elf has the same expansion bus as the Elf 2000 and stacks
perfectly with the daughter cards to form a cute little "cube". The Embedded Elf
can run the same software as the Elf 2000 and, in fact, uses the exact same
monitor firmware EPROM as the Elf 2000.

The primary differences between the Elf 2000 and the Embedded Elf are that
the latter lacks the switch interface and the TIL311 displays, although the
Embedded Elf does have eight LEDs that are used to display the POST results. The
Embedded Elf also lacks an on board voltage regulator and requires an external 5
volt regulated power supply. Finally, the Embedded Elf lacks the CDP1861 Pixie
circuit and cannot be used with either the CDP1861 chip or the STG1861 module;
however the Embedded Elf will work with the VT1802 80 column video card. The
Embedded Elf does have the same non-volatile memory and bit banged serial port
with EIA level shifter as the Elf 2000.

Please read the Spare Time Gizmos
store policies before ordering. Shipping charges shown are for
the US only - international customers please
inquire before ordering. Sales tax must be charged on all shipments to
California addresses.